" they told me Sony is not bringing in any TVs under 55inch for the 2021 TV line"
That may mean The Warehouse has dropped them. There are heavy discounts on Sony TVs there until "Offer ends 27/04/2021". I get the impression TWH only stocked them to lend credibility to those Veon horrors.
"I spoke with Panasonic which said the JX700 (40inch) is landing the end of april and will be in stores, likely the first week of May. Rrp was either $ 1300 or 1400 ( i forget exactly which price)"
TV introductory prices are high. The HX700 40" is under $800 on clearance right now.
"Bright Panel" seems to mostly be a thing which their marketing department more or less used to describe IPS panels. I'd take it with a grain of salt.
Generally people react better to bright, reflective LCD screens in shops. This a long standing thing with reflective LCDs displacing matte on laptops in the late 2000s.