Does Last stage aligners work as Retainers?

I’ve finished every level of Aligners. For an additional three months, the doctor advised me to wear the last stage. Otherwise, I’ll have to pay more for retainers.

Which method is better? Retainers are inside my budget. It’s not a problem, but I have to wait for their production and delivery.

Getting the retainers is better, in my opinion. The retainers are thicker than the standard aligner sets, that’s what I’ve seen. While retainers must maintain their shape for three months, aligners only need to be worn for two weeks. After my last pair of retainers, I received two more sets.