I've seen similar problems with some papers -- some bargain-basement Konica paper that I bought on eBay a few years ago and, more recently, some UltraFine-branded paper (rebranded, maybe from Mitsubishi?). In these cases, though, the paper tends to a slightly beige-to-yellow shade, not the more blue or cyan (on my monitor) of your sample. Thus, the cause may not be the same. In the case of the Konica paper, I only had this problem when I used a particular mix-it-yourself formula; when using commercial developers, the problem went away. I don't recall if I ever used Tetenal chemistry with this paper, though. The problem was also reduced in severity, but not completely eliminated, by cutting the development time to the bare minimum. I don't yet have enough experience with the UltraFine paper to know if the same measures would fix the problem with it.
The suggestion of a light leak is certainly worth investigating. Look for red or yellow light sources in your darkroom. Go in, shut the door, turn out the lights, but leave anything running (timers, etc.) that normally run when you process paper. Wait 20 minutes, then look around. Maybe you'll spot something you've never noticed before. In my experience, color paper is much more sensitive than most B&W papers, so a leak that doesn't fog B&W paper could cause problems with color paper. Also, a leak of red light will fog color paper to a cyan hue, but won't affect B&W paper. Since you're processing in trays, the paper gets exposure during development, too. If you have access to a drum, you could try using it to reduce light exposure a bit more. Alternatively, try processing the paper with the emulsion side down, if you normally process it with the emulsion side up.