Would anybody happen to have access to any internal or other records that might help clarify the details of the "ATC delay" to EZY 8353 (LGW-BDS) yesterday (20 Jun 23)?

The captain's post-boarding announcement stated that the aircraft (G-EZWL) had earlier been delayed in Dalaman (EZY 8563/4) due to ATC restrictions owing to thunderstorms in the area. Whilst there was certainly a number of disrupted flights at LGW yesterday evening, not all flights were as delayed as 8353. The delay map on the Eurocontrol site suggested ATC delays of approx 30-45 minutes in some sectors.

Essentially I am trying to determine the amount by which 8353 would likely have been delayed if EZY had utilised a spare aircraft - this is to pre-empt any possible "all reasonable measures" defence to the Article 19 MC99 claim I am making for taxi expenses (last bus missed despite allowing 1.5 hours' slack).

It seems to me that EZY simply stuck with the booked aircraft allocation, and possibly didn't even bother trying to get an ATC slot for an on-time departure, even though 8353/4 was operated by a fresh crew.

I'm fairly certain my claim will be rejected and I'll have to take it to AviationADR or MCOL, but I want to have as much evidence as I can to bolster my case - or to find out that it's not worth bothering, if EZY did indeed file for an on-time departure but were given a significant slot delay.

Thanks in advance