Constant Auto Fill

I main adc which is not a super sought after role. Yet I find that I am auto filled into other roles (mainly support) way more than I used to be. I am fine with playing support here and there but that isn't what's happening. If someone doesn't accept a queue, when the second one pops 90% of the time I get auto-filled. I now spend about 10 or more mins in queues trying to avoid this (gold elo). Just wondering if something in the matchmaking changed because this wasn't what it was like before.