What this means for the strip here and now is that the Lynn of 1987 is trying to process the decline in her parents as best she can by offering up the Last Days of Thelma Baird. She'd planned on there being more coins in her mother's meter but it's sadly obvious that Thelma's death next Spring is her way of trying to deal with the immediate effect of her mother's rapidly-approaching passing. Certain other things become obvious given the infamous Heintjes interview. The first obvious thing is that it took years for her to get sufficiently over the 'disappointment' that was Mrs Ridgway not tearfully admitting that she should have been a fountain of unearned praise which is why it took ten years for her to write the sappy cliche-storm of dutiful daughters and sunshine and shadow and so forth. Before that, she was still very angry with her mother for saying cruel things that proved that she detested her such us "Well, you push Aaron and Katie's characters in your strip because Elly wants them to do better; why is that wrong when I do it?"
This is also why Jim still lived on. Lynn didn't want to let him go because Mervyn wanted to let the dead rest and also didn't see that he should have beat the tar out of his wife because his kid had a screw loose and didn't want to admit that sometimes, you have to be firm with kids to make sure they turn out okay.