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I will discuss a GLIMPSE study of 230 high mass protostellar objects derived from the surveys of Sridharan et al 2001, Molinari et al 1996, Fontani et al 2002 and Faundez et al. 2004. Based on analysis of photometric data and images we find infrared counterparts to HMPOs. These point sources show high spectral indicies in the IRAC bands indicating dense envelopes and 2D radiative transfer model fits to the complete SEDs suggest B stars between 10-20Msun. Nearly 50% of the sources are surrounded by compact 8micron nebulae whose dimensions are in the range of 0.1-1pc with a mean value of 0.5pc and show morphologies very similar of UCHII regions. We argue that these are the true precursors to UCHII regions.
The overall results show early B stars associated with HMPOs that are still accreting matter. The presence of ionised gas in many of these sources suggest that ionised accretion flows may be important. These observations therefore favour a model of continuuing accretion involving both ionised and molecular components.
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