Hi John,
I'm pretty similar to you - diagnosed in May with readings over 20. I'm on 500mg metformin and 160mg gliclazide and I too tend to go a bit low mid to late afternoon. I've found that a portion of salted popcorn or a couple of crackers normally get me back on track.
I did experiment (with the doctor's agreement) with reducing my morning Glic to 40mg and also splitting my morning dose and having another 40mg at lunch. Neither of which made much of a difference to the hypos so I'm back on 80 mg am and pm.
I do find that if I have any carbs in the morning, then my levels go shooting up and then drop right down low. Yesterday I had a bowl of porridge (even though I know it spikes me) as I was tired of bacon and eggs. After two hours - 12.5 then at four hours I was down to 2.9...