I have not been able to find a definitive answer as to whether or not remote start is or was available as an option on the 2018 F-Type; I can find no coverage in the literature that came with my purchase. I have had my new one only three weeks and from what I've learned through the owner's manual and phone calls to various so-called experts, the only way to effect remote start is through the InControl feature. Can anyone out there confirm or refute this?
Also, if it is true that InControl must be active, does that mean an account must be set up with AT&T if an owner's cell phone provider is other than AT&T? According to the person I spoke to at Jaguar the sim card provided with the vehicle is for AT&T and no other sim card will work with the vehicle's system. I don't want to believe that Jaguar has provided no other method for remote start other than a smart phone app, and furthermore has restricted that functionality to one cell phone provider.
I would appreciate any comments from any source.

Can't speak to the 2018, but on my 16 it's Incontrol only activation, but my cell phone account is not through AT&T. If it's now AT&T only it's just since 2016 or 2017.

Thinking more on this,the AT&T service may be part of the 5 year plan coverage for 24 hour road service (at least in 16). I do use the remote start and if they are related to an AT&T account, I don't recall how. Maybe the Incontrol app on my communicats via AT&T account and then the info is relayed to the car?

Yes, the 2016s got 5 years of connectivity, however that is accomplished.

Update on remote start feature:
After having been told by one CSR at Jaguar that the InControl remote start feature would only work if the car came with the remote option and not being able to ascertain that remote start was even an option on the F-Type, I gave up--until today when I was fortunate enough to be connected to a different CSR who helped me set up my InControl account and the account with AT&T.
It turns out that the vehicle can be remotely started (among other things) and AT&T account is included for the duration of the warranty period.
Although I'm relieved the vehicle can be remotely started, it seems an unnecessary complication to make that capability only available through a smart phone and not with the key fob as is the case with most cars I'm aware of. Oh well.
.

Remote starts with key fobs have a limited range due to power output. With the InControl you can start your car even if you're miles away from it...I guess JLR figured that was more James Bond Q Division ;-)

I use the remote monitoring to find out that my JLR dealership hasn't worked on the car as it has been sitting in their parking bay for three days undisturbed :-(

Good point, stmcknig, but I'd have preferred both the app and the key fob capabilities just to not have to contend with two devices as I'm exiting the gym, grocery or where ever.

So I have the "in Control" app on my I-phone. It shows the condition of the car - like "windows open".
What is not clear to me is whether the 2021 MD comes with the auto start function built-in, or is this an extra?
When I use the app to turn on AC for example, the app indicates need to start engine but does not complete the action required.
So, is this an app issue or do I simply not have the auto start capability.
There is no indication of this being an "extra" on build sheet.
I must admit this is more a curiosity rather than a real need.

When the engine fails to start do you get any messages to indicate the reason? The only times my MY18 won't remote start are when the car's gone to sleep and 4 days have elapsed since it was last driven.

All functions seem to work except the auto start.
There is no separate option for auto start.
I have 3 options:
climate: does not work
door lock
beep & flash

The Climate is the remote start - no A/C without the engine running.

I am not sure I understand.
Are you saying that I need to leave the engine running (in a parking lot) in order to adjust/turn on my heating/AC using my cell phone?
Does not make a lot of sense to me. What am I missing here?

Problem sorted!!
The reason it would not start was because it was "not secure".
It was not secure because the windows were open and the doors unlocked (in my garage).
With vehicle "secured", the engine did start remotely and car began adjusting climate.

You found what you were missing - the car must be secure to run the engine!

I guess the main use for it is to cool it after it's been parked all day in the sun (not here in the UK!) or warmed up after being parked overnight in the cold.

I am still hoping to be allowed to come home to the UK for a visit later this year without having to go to hotel jail for 2 weeks!!

It's "only" 10 days ....

Ive started to have a message that says my car is in sleep mode due to four days of non use. It tells me to manually start the car to fix the issue. Restarting my car does nothing. I uninstalled and reinstalled the app, and my car is still stuck in sleep mode. Any suggestions?

Model year?

I let the subscription on the 18 Pace lapse and it was a royal pain to get it back. Same message, car in sleep mode. Wound up taking it to the dealership so they could remove the car from our account and then reinstall the car to the account. After that don’t forget to turn the car off and lock it for it to go fully asleep before trying remote app.

Have you tried driving it? Maybe that's what really wakes it up.

If you know you're not going to be using the car for a while but know when you do want it, you can set the wakeup timer through the app. That's always worked for me (when I know when I want the car woken up!).

It's a 2017 XE
My dealership isnt close so I dont look forward to taking it there. I was going to try calling Jaguar USA if thats even possible. I renewed my subscription in Decmber, so I know it's not because of it lapsing either. It just randomly stopped working. I'm retired so the car may have very well sat undriven for four days which is what put the car in sleep mode.
Thanks for your input. I'll keep trying!