My prediction is that the far reds will reverse the shortening effects of the 5000k. Whether it will speed up ripening or cause more flowering idk, but I know for sure it will cause the standard FR effects; longer internodes and more stem weight with the same weight of everything else, long petioles and leaves angled sharply upward. I have found that 5 min of normal red at lights out reduced stretch and didn't seem to impede ripening any. I was using two 13w red CFLs with a 220w 4000k high bay, 5 min before white light on, then staying on with the whites and remaining on for 5 min after the whites go off. Now I have upped it to 4 CFLs and 15 min before and after. So far so good. I know people think red light causes stretching but that's only if you use red and nothing else. 5-15 min end of day actually reduces stretch, because it reverses the effect of the far red that is already in the COB spectrum, though much less than HPS. When I used the 4000k COBs alone, they had the normal FR stretch syndrome and 5 min EOD FR just made it even stretchier. I gave that up quickly. BTW, with the reds I have them on a 12/12 cycle and the whites on a 11.5/12.5 cycle in the middle of the red cycle, so the total day length is still 12 hours.
Also I'm not even bothering with the lizard lights anymore because I didn't find they helped noticeably and may even have reduced potency by destroying some of the THC. Don't know if that's what happened but I'm pretty sure I would do better to just keep going with the enhanced red spectrum. I haven't read any complaints about LED weed being less potent than imports from high UV regions. It's also a huge pain because the UV lights only last about 6 months-a year and they have to be positioned very close. Just doesn't seem worth it to me. If I noticed a big increase in potency then maybe, but I haven't.