Yesterday's strong rebound from 90.07 suggests the erratic fall from last Friday's high at 91.3 has ended and a breach of 91.08/15 would signal recent upmove from 88.01 (the 8-1/2 month low made earlier this month) has resumed for a re-test of 91.33 and then further gain towards 91.70/80.  
On the downside, below aforesaid support at 90.07 would abort and risk stronger correction to 89.60/70 before prospect of a recovery.