Hey gang a quick question for you. I have an opportunity it to do my CPL with an instructor that I like and is in my area, but I don't necessarily have the need for it right now, it would be for the future. Thinking commercial float flying and ferry pilot down the road.
The CPL comes with much more stringent and frequent medical test under the cat 1. Once I have the rating, if I let my medical lapse and just do my cat 3 medical, I would obviously not be able to act on the privileges of the CPL but do I lose the rating?

If I went a couple of years flying on my ppl with a Cat 3 medical every 2 years and then decided to get my Cat 1 again would my CPL be valid again or would it have expired? Can I just go and get a cat 1 medical when I see an opportunity to use the licence and then let it lapse again or does the medical need to be maintained throughout with no interruptions.

I'd love to get the rating for when I want to use it but just not crazy that it involves 4 cat 1 medicals( 1 x every 6mo) vs my single cat 3 medical every 2 years. Seems like an expensive thing to maintain from a medical apt standpoint if I'm not going to use it immediately. That vs I have the time and the instructor now.

Thanks for any insight and experience.

K

If I went a couple of years flying on my ppl with a Cat 3 medical every 2 years and then decided to get my Cat 1 again would my CPL be valid again

yes

Short answer yes. In fact, if the cost of a Cat 1 and Cat 3 medical is the same for you, go ahead and do a Cat 1 every two years. You will have CPL privileges for 6 months then PPL privileges for a further 18 months.

Nuanced answer which you'll need to understand for your written exam:
Licences don't expire or change (eg. from CPL to PPL)
Medicals don't expire or change (eg. from Cat 1 to Cat 3)
You are allowed to exercise the privileges of a licence based on the type of licence you hold and the time since your last medical and its category.