Make of that what you will. You're right though - I seem to remember that she can only unilaterally revoke until the end of March, so that presumably is the default option that she's being steered towards (with another referendum as a fall back)
I don't think she'd ever consider revoking. She's likely to be forced out of office either way, but revoking would see her labelled by the Brexiters as a traitor and she might well think that would be true.
I can just about imagine a situation where the ERG forces her out in an attempt to get No Deal and she revokes out of spite to prevent it or something. The very last card she's got to play.
Sh categorically denied earlier today that she would revoke:
https://mobile.twitter.com/Peston/status/1107983373195202560
Make of that what you will. You're right though - I seem to remember that she can only unilaterally revoke until the end of March, so that presumably is the default option that she's being steered towards (with another referendum as a fall back)