do it now so usually 6 months before

6 months before expiration.

thanks

My application expires in September. Following my lawyer's instructions, I submitted it in March 19th due to all these delayed responses from immigration.

6 months before but I suggest submitting paperwork now because I applied in January and still no receipt notice receive and my docs had expired

Mine expired 25th April. I submitted January and was approved 29th April for 5 years. Took 3 months. Start yours now.