Congratulations on doing a full rotation on the bike!

Well done for continuing to refuse weights or pushing on your knee. You're making good progress with both flexion and extension. It's not unusual for full extension to take longer to achieve than flexion does, so don't worry about it.
No doubt, your PTs have an agenda for your knee to achieve certain numbers. Don't buy into that. Your knee has its own recovery agenda and it will achieve ROM at its own speed.
ROM, both flexion and extension, can continue to increase for a year or longer after a TKR. There's no need to rush, no deadline you have to meet:
Myth busting: the "window of opportunity" in TKR

Well done for continuing to refuse weights or pushing on your knee. You're making good progress with both flexion and extension. It's not unusual for full extension to take longer to achieve than flexion does, so don't worry about it.
No doubt, your PTs have an agenda for your knee to achieve certain numbers. Don't buy into that. Your knee has its own recovery agenda and it will achieve ROM at its own speed.
ROM, both flexion and extension, can continue to increase for a year or longer after a TKR. There's no need to rush, no deadline you have to meet:
Myth busting: the "window of opportunity" in TKR
New Zealand