Grape vine where we're replacing a pagoda
I'm helping out on someone else's allotment (on 20 March) - we're clearing a space which currently has on it a very rickety pagoda-type structure, and replacing it with a larger and more substantial structure.
The thing is, there is a grape vine growing near one of the existing posts (which will be removed). It is tied to the existing roof, but isn't really wound round it/attached to it at all (nor to the post). We plan to put in a post next to it within the new structure, and tie the vine in to this internal post and then the roof.
I need to know how best I can protect the vine from damage during the removal and construction process, especially as there will a few guys helping out who are not gardeners and who I suspect won't be quite as careful as me!
I don't think it has been pruned particularly in recent years; it seems to be one long stem really, perhaps 4m long. I know it is not the right time of year to be pruning it, so I presume that cutting it back now would be pretty detrimental?!