I saw this mentioned on the Monzo forum. I checked my RBS account and initiated one. It’s not activated yet because for some reason RBS are unable to activate virtual cards immediately unlike Wise or LHV for example. I may use it, I may not 
I just mentioned it in another thread 
Good feature, the wait is probably because of some reconciliation batch process or something that happens I would assume.
Nice to have though. RBS have been doing a lot of work over the last year or so
Yes, it’s bizarre that we both posted the same thing at the same time! 
I was typing and didn’t realise you had already posted, just a huge coincidence.
I guess my virtual card will just be that purple plain thing rather than a virtual replica of my Holts Squirrel card. I wait and see.
It didn’t take long to activate for me. The weekend didn’t seem to make a difference it was available within a day
Works with Apple wallet etc as well.
Mine is now activated. It just took overnight for it to happen.