Gaps often appear in the course of trading and they don't all need to be filled. The type of gap will determine whether or not they get filled.
From my recent understanding there are five main types of gaps
1. Common gaps -usually get filled
2. Exhaustion gaps – get filled
3. Island reversals – get filled
4. Breakaway gaps – don’t need to be filled
5. Runaway gaps – don’t need to get filled
I think GBR’s gap was most likely a runaway gap as it was also combined with very high relative volume.
It’s a positive thing and doesn’t need to be filled however if it does retrace to the pre-gap point then it can create a strong support base for renewed buying.
It’s very interesting and explained very well on Investopedia and makes for a great read.
This is the GBR chart and is interesting to compare to the examples in the following link:
