diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 02b1471f52..8e53b950e1 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -214,6 +214,8 @@ test-dev-cran-lin: ## R-devel on Linux, --enable-strict-barrier --disable-long-d
   variables:
     _R_CHECK_CRAN_INCOMING_: "TRUE"
     _R_CHECK_CRAN_INCOMING_REMOTE_: "FALSE"
+    _R_S3_METHOD_LOOKUP_BASEENV_AFTER_GLOBALENV_: "FALSE" ## detects S3 method lookup found on search path #4777
+    _R_S3_METHOD_LOOKUP_REPORT_SEARCH_PATH_USES_: "TRUE"
   before_script:
     - *install-deps
     - *cp-src
diff --git a/DESCRIPTION b/DESCRIPTION
index 06b7f33c3d..913b9e74a9 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -63,7 +63,7 @@ Authors@R: c(
   person("Dirk","Eddelbuettel",    role="ctb"))
 Depends: R (>= 3.1.0)
 Imports: methods
-Suggests: bit64, curl, R.utils, xts, nanotime, zoo, yaml, knitr, rmarkdown
+Suggests: bit64 (>= 4.0.0), bit (>= 4.0.4), curl, R.utils, xts, nanotime, zoo (>= 1.8-1), yaml, knitr, rmarkdown
 SystemRequirements: zlib
 Description: Fast aggregation of large data (e.g. 100GB in RAM), fast ordered joins, fast add/modify/delete of columns by group using no copies at all, list columns, friendly and fast character-separated-value read/write. Offers a natural and flexible syntax, for faster development.
 License: MPL-2.0 | file LICENSE
diff --git a/NAMESPACE b/NAMESPACE
index c2c095a1d8..57271aa04d 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -151,8 +151,7 @@ S3method("+", IDate)
 S3method("-", IDate)
 S3method(as.character, ITime)
 S3method(as.data.frame, ITime)
-S3method(as.Date, IDate)   # note that zoo::as.Date masks base::as.Date. Both generic.
-export(as.Date.IDate)      # workaround for zoo bug, see #1500. Removing this export causes CI pipeline to fail on others.Rraw test 6, but I can't reproduce locally.
+S3method(as.Date, IDate)   # note that base::as.Date is masked by zoo::as.Date, #1500 #4777
 S3method(as.IDate, Date)
 S3method(as.IDate, POSIXct)
 S3method(as.IDate, default)
@@ -187,10 +186,3 @@ S3method(unique, ITime)
 S3method('[<-', IDate)
 S3method(edit, data.table)
 
-# duplist
-# getdots
-# NCOL
-# NROW
-# which.first
-# which.last
-
diff --git a/NEWS.md b/NEWS.md
index a2318dda88..826573d7b2 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -14,6 +14,8 @@
 
 1. Continuous daily testing by CRAN using latest daily R-devel revealed, within one day of the change to R-devel, that a future version of R would break one of our tests, [#4769](https://github.com/Rdatatable/data.table/issues/4769). The characters "-alike" were added into one of R's error messages, so our too-strict test which expected the error `only defined on a data frame with all numeric variables` will fail when it sees the new error message `only defined on a data frame with all numeric-alike variables`. We have relaxed the pattern the test looks for to `data.*frame.*numeric` well in advance of the future version of R being released. Readers are reminded that CRAN is not just a host for packages. It is also a giant test suite for R-devel. For more information, [behind the scenes of cran, 2016](https://www.h2o.ai/blog/behind-the-scenes-of-cran/).
 
+2. `as.Date.IDate` is no longer exported as a function to solve a new error in R-devel `S3 method lookup found 'as.Date.IDate' on search path`, [#4777](https://github.com/Rdatatable/data.table/issues/4777). The S3 method is still exported; i.e. `as.Date(x)` will still invoke the `as.Date.IDate` method when `x` is class `IDate`. The function had been exported, in addition to exporting the method, to solve a compatibility issue with `zoo` (and `xts` which uses `zoo`) because `zoo` exports `as.Date` which masks `base::as.Date`. Happily, since zoo 1.8-1 (Jan 2018) made a change to its `as.IDate`, the workaround is no longer needed.
+
 
 # data.table [v1.13.2](https://github.com/Rdatatable/data.table/milestone/19?closed=1)  (19 Oct 2020)