I'm pretty sure it's the bridged appearance. There are limitations on the number you can add.
User BSH posted this previously:
page 7 and note 15 on page 19
There can be up to 16 Bridged Call Appearances for a primary?s extension (not
call appearance button) if ASAI is used.
Otherwise there can be 63 Bridged Call Appearances for a primary's call
appearance, up to system limit of 1250 primary call appearances.
The limit is 25 Bridged Call Appearances for each primary after that, up to the
system-wide maximum number of bridged appearances.
With Special Application SA9018 the number of Bridged Call Appearances for a
primary's call appearance is increased to 127.
A great teacher, does not provide answers, but methods to teach others "How and where to find the answers"
bsh
37 years Bell, AT&T, Lucent, Avaya
Tier 3 for 27 years and counting