In The Morning When I'm Real / Porcelain Mirrors
(45 rpm single)

Original release:
45 rpm single: Vanguard VRS 35087 (1969)

In The Morning When I'm Real
2.   Porcelain Mirrors

Duane Allman plays on track 1.

'In The Morning When I'm Real' is probably the same version that was released as a bonus track on 2009 CD release of 'The 31st Of February' (Henry Stone Music USA, Inc., HSM 5041-2).

The same backing track (but without the horns) was used
for the 1972 LP release 'Duane & Greg Allman' (Bold Records 33-301):

It is possible that Vanguard took the backing track from the September 1968 sessions (with Duane and Gregg Allman and released on the Bold LP), added horns and released it as a single.
Another possibility, however, is that the backing track was not recorded at the September 1968 sessions at all, but was a leftover from the sessions for the '31st Of February' Vanguard LP. In that case Duane and Gregg Allman don't play on the track. It is the only track on the Bold Records LP where Gregg Allman doesn't sing the lead vocals.

Update November 4, 2013:

On November 4, 2013 Scott Cantor spoke with Steve Alaimo, one of the producers of these tracks. He confirmed that Duane and Gregg Allman played on 'In The Morning When I'm Real', recorded at the September 1968 sessions at the Tone Studios in Hialeah, FL. with the '31st Of February'. These sessions were released in 1972 on the LP 'Duane & Greg Allman' (Bold Records 33-301).
Steve Alaimo added horns to the recording of 'In The Morning When I'm Real' and released it as this single in 1969.

(Thanks to Scott Cantor for this information and for contacting Steve Alaimo)