Well I passed my mod 4 last week and sent my licence away to hack my cat c added also updated my photo and am astonished that 4 days later I received it back. That’s gotta be some kind of record.
That was quick hey. 
what amazes me is my ex partners mom worked at DVLA in Swansea in the driving licence section,
Now when I applied for my first provisional I had it done and dusted and back the same day, Again once I had passed my test again she took it in on the morning with the pass cert and low an behold had it back the same day again.
So I have never understood how they quote the timescales they do. lol
but that is fast in fairness