Mountain Chiffchaff id (1 Viewer)

I am looking into the identification of Mountain Chiffchaff , of the Caucasian race lorenzii, away from it's normal range.

Apart from differences in plumage and call, has anybody noticed in particular, a difference in jizz or movement between lorenzii and collybita.
For example, is the shorter winged/longer tailed look noticeable. Does the bird look more compact.
Is the bird more active with faster movements, less pausing, more akin some of the smaller phlloscs?

Also, does anybody know if there is a difference in moult strategy? Would a bird showing moult in May preclude this species?

Thanks in advance for any replies.

Good luck... sorry I can't help, despite a big thing for Phylloscs.. welcome anyway - hopefully someone with experience of lorenzii will reply....I'd like to know the answer too. They always look so tiny in photographs!

Having seen a few Mountain Chiffs in northeast Turkey I should be able to answer this but I can't say I noticed anything really striking other than them looking rather plain and quite dark brown above than a collybita. I think they're probably a lot less obviously different to collybita than a lot of Chiffchaffs that are regarded as still being the same species (e.g. Iberian, tristis types). I'll have to look a bit harder if I go back to Turkey!

Thanks Jane and Fifebirder for your replies so far.

We are trying to identify a bird seen earlier this year, and are wading through lots of information on all the possible chiffchaff subspecies/species.

During our research, we have heard that a Mountain Chiffchaff has apparently been accepted in Gibraltar recently, so it may indeed be one to keep an eye out for.

Tim