Ask yourself why Gillian is so friendly with the cast and crew of The Crown. It’s not because she’s appearing in it. Season 2 is halfway through filming and it would’ve been announced by now if she was going to be in it. She wouldn’t be hanging out with people she hadn’t worked with yet, either. The most likely explanation is that she knows them so well because she’s dating their boss and sees them regularly.

I’m sure you can think better than this. “She knows their boss!” Seriously? Look, if she’s with him, why didn’t he march with her? If the crown was filming, why isn’t he on this pic rather than the producer? Do you seriously think that if she’s dating PM she spends all her free time hanging out with her boyfriend’s coworkers? Who does that? He probably doesn’t do that himself.
This guy was at their table at the GG, she probably met him at the Premiere, or maybe she knew him before, it’s a small world.
There’s an article which just came out about The Crown season 3. They’re recasting everyone because the characters need to be older. Gillian could legit be in it, there might be a lot of discussions about it right now, she could be a producer too, she could be a lot of thing about this show. It doesn’t mean she’s not dating PM, but it doesn’t mean she is either.
There is something about this show, and I’m like 99% sure about that.