Question about silicon valley clean energy and NEM

I have a solar installation and buy energy from SVCE through PG&E. I understand both maintain separate NEM balances. For example, in the last month I generated -$150 of excess energy but my NEM balance on PG&E only went down by $70. The other $80 credit was routed to SVCE. My current balance for SVCE is -$150 while the balance for PGE is +$30.

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What happens at the end of the year? Is it possible that I need to pay PG&E NEM charges at true-up while SVCE converts the remaining large balance into a pittance at the nominal tiny payback rates. Stated differently, is it possible to sum both NEM balances and then settle or are they settled independently