Awning suitable for a high coach built

Hello all, my name is annie and I wanted to say hello and that I have found the discussions invaluable when we chose a weingsberg meteor motorhome.  We have just taken delivery of it today, having been caravanners for a number of years.  I would be ever so grateful for some advice on a suitable awning. There is a rail to attach an awning at about 256cm from the ground.  This sits below a wind out omnister.  We would love to purchase a kampa rally, however their specification for height gives 235-250cm.  Would we be pushing the height too far if we are slightly over?  I wouldn't want to spoil the kampa awning and place the rail under any extra strain.  Any advice would be very much appreciated.