Continuing Issues at Night

I’ve had my Lena Cup large for 3 cycles now, and during the day, I love it. I don’t have problems with leaks whether sitting, standing, bending over etc. I’m pretty sure that it is forming a seal when I insert it because I hear (and sometimes feel) suctioning, and when I run my finger around the rim of the cup it is completely open and pressed up against my vaginal wall. 

Nighttime is unfortunately a different story. Most of the time after waking up and walking to the bathroom, there will be some amount of blood on my pantyliner/pad, and it appears to be happening at the change in position. It’s not enough blood to leak out into my pajamas or sheets during the night, so the cup probably isn’t leaking all night. It’s not residual blood either because I can feel it leaking out when I get up. In fact, I tried an experiment this morning and laid down in my bed after getting a shower with the intention of checking my seal while laying on my side as I do when I sleep. Everything seemed fine, but when I stood up (after laying down for just a minute or two), I began leaking. It’s enough blood that it can’t possibly be coming out of the air holes. 

I’m wondering what the problem could be. Lena Cup’s customer service has been helpful, but most of their suggestions deal with seal problems and I’m just not sure that this is what this is. I’m pretty sure that my cup sits around my vaginal fornix, so the capacity may be somewhat compromised, since when I take the cup out in the morning after it has leaked most of the time it is only half full. Could it be that the cup is too firm and is not conforming to my body while I’m laying down, but is losing suction instead? 

I’m not opposed to trying another cup, but since I don’t really know what the issue is, I don’t know what kind of cup I need to resolve it. My cervix is of average height during my period and I am a pretty heavy bleeder (Empty 2-3 hours after first morning emptying, then every 3-5 hours afterward on heaviest days, although cup isn’t ever more than half to two-thirds full when I empty during the day.) I’d really like to find a way to get through a night without feeling like I need to wear a pad for when I stood up. After all, I bought the menstrual cup with the intention of not using pads or tampons again.