For me with my 2 RX 580 change is:
14.5 each to 20 sol/s (+38%)
Go this way, when it reaches 100 sol/s per card it will be profitable

Thats odd - before yours was much faster, now slower. Hmm ... most changes targeted the memory controller, maybe different vendor of mem chips?
My testing gpu is a saphire pulse 4g at stock clocks, what is yours?
One with 4GB Elpida memory with best timings available in this forum & speed set to max. 1999 MHz, GPU at 1250 MHz.
The other with 8GB Hynix also with best timings at 2050 MHz & GPU at 1250 too.
Both cards give me the same speed, about 14.5 with 0.41 & 20 with 0.42 (average, not peek).
Blockchain drivers & Windows Server 2008 R2