System is sealed so it should not bleed out but I wouldn't do anything about it yet. Once you get it running see if it goes back to normal height. Assuming it does, let it sit overnight and see how much it drops. May not be leaking enough to have to do something right away but do have to address it before the compressor starts running too much of the time. Will have to do some troubleshooting to be sure which component(s) are leaking.

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X5 4.6 2002 Black Sap, Black interior. 2013 X5M Melbourne Red, Bamboo interior
Dallas