Tricky, which Roberts frame numbering can be: post 1979 they - apparently - changed to a six digit numbering system but deviated from that when building frames for the trade ! Five digits would suggest pre 1979...I think it is early and a Penge frame but sticking my neck out. My two early frames have three digit numbers and are Sydenham frames.
Based on what's been said in the Roberts thread previously, I'd interpreted it as year/month/frame number (of that month). Does that sound right to you?
Tricky, which Roberts frame numbering can be: post 1979 they - apparently - changed to a six digit numbering system but deviated from that when building frames for the trade ! Five digits would suggest pre 1979...I think it is early and a Penge frame but sticking my neck out. My two early frames have three digit numbers and are Sydenham frames.