The lug detail looks a lot older than the fork crown, the dropout looks 90s, but the spacing...?
I think the back end has been crushed in (from 126) by a hipster riding a 120 fixed hub.
The stays look a little pulled in to me.
Used to see loads of this in the fixie boom of 2006
Details of the brake bridge and chainstay bridge might help to thin out the options. I am not familiar with Holdsworth's frame details of any era. What @bikeworkshop says makes sense, but seeing 2 sets of bottle cage mounts, bottom of BB cable routing keeps it more 80s era and later except for the Nervex lugs (did Holdsworth use them that late in time?). I cannot discern if stays were "coldset" or just bent in, but I would expect a 125/126mm rear spacing for the assumed era it was built.