I've started playing the concertina (20 button C/G) only weeks ago, and luckily I managed to find the fantastic tutorial by Alan Day.
In lesson 4 when he introduces Oscar Wood's Jig on the C row for the first time, I can't seem to figure out what the left hand is doing. I can play through the right hand pretty well now, but I'd like to try introducing the bass notes on the left hand. I think the  and  sections, (see attachment), have something to do with it but I'm not quite sure.
Does anyone know which buttons are being pressed on the left hand and/or which beats they are played on?
Thank you so much in advance!!
(Attached is the sheet music for Oscar Wood's Jig on the C row)