I’m not familiar with SCART but if it’s similar to HDMI it’s possible you have the HDMI(or in your case SCART) control, turned on.
Check the menus of your TV or DVDR for cntl. or control and make sure it’s OFF. It’s the only think I can think of and as to why it’s turning your TV on. It could have something to due with a guide service being downloaded during the night causing your DVDR to come on, which in turn could?? turn your TV on.
Kind of a guess but could be.