Agree with Asturias56. My wife was detained at CPT in 2020 (departing to UK) because the immigration officials could not reconcile the expiry of her Retirement Visa.
"This is a four year visa, 2016, 2017, 2018, 2019. It is expired so we have to deport you". It took an uncomfortable hour, the eventual arrival of the Head of Immigration and a phone call from our pit bull immigration lawyer to convince the said chap and chapesses that years are actually 2016-2017, 2017-2018....well you get it. Luckily BA58 was late as usual so she didn't miss her flight!
Get it renewed as its simply not worth a squeaky moment at immigration.