Thanks, Phillip. Figured out the issue in case anyone else experiences the same. Any saved search which has a result field that is sourced from a custom Subsidiary field and has Store Value turned off fails in both the script and the UI. NetSuite support believes the bug was pushed into TSTDRV and sandbox accounts with an e-fix this morning - a U3 defect has been issued as a result. Fingers crossed they push back introducing the e-fix scheduled for production environments tomorrow…. anyone else experiencing the issue submitting a support case would help that cause.