[aprssig] Delayed packets

[Robbie, wa9inf]

I seldom use the APRS-IS for input to my aprs station, except for NWS, 
and for tracking my friends on their trips.

There is a station 85 miles from the station I am tracking. Since I am 
getting the station I am tracking from the APRS-IS via a filter, I see 
all the I-Gate stations callsigns.. This one station constantly has my 
tracked station jump backwards with a "delayed" packet by as much as a 
two minute delay...

Is this a Findu issue of Dupe checking because too short of dupe 
checking time cycle, or, how could the I-Gate in question delay 
I-Gateing by as much as two minutes, and have the tracked station jump 
backwards with his delayed packet?

This station does this on a regular basis for any mobile I have tracked 
via the internet that gets its packet digipeated out to the Rockford 
area from the Chicagoland area. The sysop said he does not know why his 
I-Gate could do this.

I do not know, and I haven't heard about a means of  an I-Gate client 
being able to dupe check stations it is about to put on the APRS-IS, but 
I sure can see that in this case, they all should??

Robbie