Difficulties with wearing a device? discussion

2 part question I suppose… I’ve had my Jailbird for almost 2 years. Longest I’ve worn it continuously without a break was about 4 months. I have a MM Jailbird. Couldn’t be happier with it! I followed the measuring instructions on their website, and subtracted a 1/2 inch for my order. When I’m normally flaccid it fits perfectly. However, after exercise or swimming (shrinkage), i’ll have a good half in space at the end. So, does this mean it needs shortened? Second, typically i sleep naked wearing just my Jailbird. Night time erections have become a pain, literally. Since the cage fits perfectly flaccid, when I become erect at night, the whole cage starts pulling away from my body. Does this mean I need a smaller base ring? On MM website it said that if you can get a finger under the ring (and no more) it’s probably the right size. That’s how it fits. Would it help to wear tight underwear to bed to help hold it in place? Thanks in advance, and any info/help is greatly appreciated!