Honestly I find if I spend too much time thinking about how old people are in the DCU I end up with a big headache. My friend came up with a theory she calls the "Liane Harper" factor which relates the passage of time in the DCU to Liane's aging 4 and half years over the last 20 plus years. This kind of works depending on where you start from.
As far as Dinah's shirt, etc. I am using the "let's ignore it all happened" tactic to everything Kriesberg has done to Dinah.