Creating a quotation number with YYMM prefix and counter afterwards


I’m quite new to SuiteCRM and got a question to create a new field Quotation Number that is populated when an opportunity is created. The first 2 numbers should be the Year, then Month and then 6 for a unique ID.

I found out how to create the 2 parts of the ID seperately but don’t really see how to combine them into one number. Any assistance is super welcome!

{now(ym)} {GlobalCounterPerModule(quotationnumber;6)}

Bonus question, users want to be able to edit this number in some niche cases but in general I would prefer to keep it auto generated.

kind regards