If one prayed Maariv while it was still day without having yet worn tefillin, may one still don tefillin afterward?

Synopsis

One who accepted Shabbat or night early by praying Maariv, having not yet worn tefillin, faces a conflict between two inconsistent leniencies (treating it as night for prayer while treating it as day for tefillin). The Mechaber cites an opinion that forbids subsequent tefillin-donning.

Early Acharonim
Late Acharonim
Lenient
Strict
Lesser cited
Major authority

Discussion

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