Sources:
2015 Asian Highway logca. 2020 Bangladesh RHD road network maps (select the map, then open image in new tab)
Online Road Network databasethe occasional sign that actually mentions route numbersBGD AH1
IND/BGD
add N2_N (the road to Jaflong is N2)
add Z2012
add Z2011
add N210
add R248
move R280 west to the next major intersection
add N205_E (where OSM's trunks split just south of R280)
N208
add N205_W
add Z2013 (the first road to the south, just west of N205_W)
add R283
Z2016
N207_N -> N207_E
R241
add R240
Pan
N207_S -> N207_W
N204_E -> N204/R240
add R221
N204_W
move Mad north to the center of town
E220 -> R220
N102
move ChoChaRd just barely east to Z2031 (the very next road south)
R360
add Z2032 (the road east of the building marked Shantiniketan on OSM)
add Z2041
add Z2042
R211 -> R211/310
add R210
R301 -> R301/Z2047
add Z2038
add R203
N105
add R202
R201
N1/N2 -> N1_E
DemNarRd -> R110_E
add R111
add Z1102
add Z1101
N1/N8 -> R110_W
R810 -> N532
Bas ->
BasRiv and move west to the underpass (where the road crosses on the almost perfectly east-west portion)
add N802
add
Abdadd Z5069 (first intersection north of the shaping point) - or not because it only accesses the frontage road?
(the next few routes - Z8005, Z8203, Z8003 - only access the frontage roads, and I don't see any slip ramps)
R820 -> R820/Z8004
(R821 has no main lane access)
move R812 north to the circle (if that's what's still there)
delete MawaKarFry; there's now a bridge
add
Canadd R863
(Z8013 only has frontage road access)
add Z8014 (or is it only frontage road access now?)
Shi -> R862 (but it may have only frontage road access)
add
PulBaz(Z7108 only has frontage road access)
N8/N804
West of here, the route is all wrong, since it uses the new Madhumati Bridge. So delete N803 thru N7/N702_S and replace with:
Z8067
Z8021
Z7004
Z8023
Z7001
N805_S
Z7507
Z7503
Z7505
Z7502
R720
Z7030
Z7504
Z7501
N707_E
N708
N702/707
N7_S
N7/N706 -> N7_N
add Z7551
add R765
add N711_E
move Ben west to N711_W
BGD/IND