Incr / Decr with TTL doesn't change TTL value

Ubuntu 12.04.5
Python 2.7.3
CB 3.0
LCB Version= 2.4.3
Python SDK - 2014-10-06 10:33:08.652762 _version_ = '1.2.4'

Setting a new TTL value to a document during an increment or decrement call doesn't change the TTL value for the document. Am still testing this against other SDKs/LCB as well

Have this is a try/except block to print any errors, no errors are printed.

=========

print "Setting foo now"

c.set("foo", 18446744073709551615, ttl=300)

try:
data = c.get("foo")

except CouchbaseError as e:
print "Couldn't retrieve value for key", e

1. Rethrow the exception, making the application exit
   raise

====

print out the key_exptime

then run

====

print "Incrementing with TTL"

try:
c.incr("foo", amount=100, ttl=10)

except CouchbaseError as e:
print "Couldn't incr value for key", e

1. Rethrow the exception, making the application exit
   raise

=====

The value is incremented as expected.
print out key_exptime and it hasn't changed and doc still exists.