diff --git a/.github/workflows/build-npm-release.yml b/.github/workflows/build-npm-release.yml
index 47510d51..75d20a0a 100644
--- a/.github/workflows/build-npm-release.yml
+++ b/.github/workflows/build-npm-release.yml
@@ -27,7 +27,7 @@ jobs:
       PUBLISH_MOD_DESCRIPTOR: 'true'
       FOLIO_NPM_REGISTRY: 'https://repository.folio.org/repository/npm-folio/'
       FOLIO_MD_REGISTRY: 'https://folio-registry.dev.folio.org'
-      NODEJS_VERSION: '16'
+      NODEJS_VERSION: '18'
       JEST_JUNIT_OUTPUT_DIR: 'artifacts/jest-junit'
       JEST_COVERAGE_REPORT_DIR: 'artifacts/coverage-jest/lcov-report/'
       BIGTEST_JUNIT_OUTPUT_DIR: 'artifacts/runTest'
diff --git a/.github/workflows/build-npm.yml b/.github/workflows/build-npm.yml
index fbfd2eca..afe48470 100644
--- a/.github/workflows/build-npm.yml
+++ b/.github/workflows/build-npm.yml
@@ -22,7 +22,7 @@ jobs:
       PUBLISH_MOD_DESCRIPTOR: 'true'
       FOLIO_NPM_REGISTRY: 'https://repository.folio.org/repository/npm-folioci/'
       FOLIO_MD_REGISTRY: 'https://folio-registry.dev.folio.org'
-      NODEJS_VERSION: '16'
+      NODEJS_VERSION: '18'
       JEST_JUNIT_OUTPUT_DIR: 'artifacts/jest-junit'
       JEST_COVERAGE_REPORT_DIR: 'artifacts/coverage-jest/lcov-report/'
       SQ_LCOV_REPORT: 'artifacts/coverage-jest/lcov.info'
diff --git a/src/forms/CalendarForm/validation/validateExceptions.tsx b/src/forms/CalendarForm/validation/validateExceptions.tsx
index 01c7ed17..8413ecb9 100644
--- a/src/forms/CalendarForm/validation/validateExceptions.tsx
+++ b/src/forms/CalendarForm/validation/validateExceptions.tsx
@@ -250,10 +250,10 @@ export function validateExceptionInterOverlaps(
       i: row.i,
       startDate: dayjs
         .min(row.rows.map(({ startDate }) => dayjs(startDate)))
-        .startOf('day'),
+        ?.startOf('day') ?? dayjs(0),
       endDate: dayjs
         .max(row.rows.map(({ endDate }) => dayjs(endDate)))
-        .endOf('day')
+        ?.endOf('day') ?? dayjs(0)
     }));
 
   for (let i = 0; i < rowMinMaxes.length - 1; i++) {