That might be.
My current understanding is that the arrows indicate the direction of travel (on the paper) to from ROMIR to VEDOK.
The arrows are always pointing north and south. So I assume you would use standard Icao rules as stated in the AIP as well.
I’ve had a situation last year where I got a call from the Dutch ARO about a flightplan I filed with Autorouter.
They said I should not use Autorouter and my filed route was illegal 
Apparently there was a bug in the Eurocrontrol IFPS rules. It’s the job of each ANSP to program these rules.
You can’t blame Autorouter for finding a route that validate OK but is illegal.
This was the filed route, which validated OK by Eurocontrol:
Dear Len,
you have just successfully filed a flight plan with the following details:
Callsign: PHPCA
Departure aerodrome: LFQQ – LILLE LESQUIN
Destination aerodrome: EHLE – LELYSTAD/LELYSTAD
Estimated off block time (EOBT): 2016-04-13 05:30Z
First alternate: EHGG – GRONINGEN/EELDE
Filed route: N0135F090 CIV4E CIV DCT BARTU/N0132F060 DCT RUPIN DCT GISEB VFR
The problem was that the Dutch border is crossed with a DCT. This is not allowed.
Can anyone find another good route in a even flightlevel? FL100? Or 80?
Apparently there was a bug in the Eurocrontrol IFPS rules. It’s the job of each ANSP to program these rules.
You can’t blame Autorouter for finding a route that validate OK but is illegal.
That sums up European integration generally and Eurocontrol specifically 
Eurocontrol IFR doesn’t normally need the right semicircular level. Most ATC regions don’t care; separation is done tactically with radar control. But some do, especially on a handover to them from another one.
Can anyone find another good route in a even flightlevel? FL100? Or 80?
I wouldn’t bother. Most light GA IFR is done VMC on top anyway, so you just climb up and when in sunshine you stop at either the filed level or at FL090/100 or so. You can say “request stop climb FLxxx”. Or keep climbing as high as necessary (usually needs oxygen).
Quite strange. Same route: EHLE VEXAR SIPSA RALEL EDDV
I suggest you file a bug report @Flyamax
Can anyone find another good route in a even flightlevel? FL100? Or 80?
Just add the level change at ROMIR if you want to fly N851 at FL080? But as Peter said: In the end it will not matter what you file as it is all radar controlled.
LSGG N0135F090 SPR4N SPR G5 WIL T125 ROMIR/N0134F080 N851 TEDGO DCT OKIBA DCT LEPSA VFR EDGF
Thanks.
I have just done this on FlightPlanPro for for a higher level.
(FPL-NXXXXX-YG
-TB20/L-YGSR/S
-LSGG1000
-N0172F110 MOLUS N871 BERSU/N0178F140 N871 DITON T163 ZUE T125 ROMIR N851 TEDGO N624 TOSTU VFR
-EDGF0150
-PBN/B2D2 DOF/170202)
dfjohansen wrote:
That might be.My current understanding is that the arrows indicate the direction of travel (on the paper) to from ROMIR to VEDOK.
The arrows are always pointing north and south. So I assume you would use standard Icao rules as stated in the AIP as well.
The ENR Chart LOWER Airspace also shows odd levels northbound, and even levels southbound for N851:
