I promised a few pictures to illustrate mixing telegraph pole types.
In the first picture are two line of telegraph poles and the left hand set are diminishing from 8 bars down to 4, 2 then1 bar. Whilst this shows a variation in number of bars you can also see a variation in height of pole.
This is achieved by placing a string of Wire Connector poles then selecting a second Wire Connector string, control left click on the final telegraph pole of the first string (this joins the two strings together) then start laying the second string. Rinse and repeat, as required.
Using this technique and carefully numbering the connectors it is possible to split a run of wires into two.
In order to carry the telegraph wires over Belah viaduct it was necessary to come up with a variation on this method. Firstly a set of special lofted wire supports for the bridge were developed.
A line of telegraph poles are run up to the viaduct but they can't be connected to the bridge lofted wires in the same manner as above. Firstly, it is necessary to delete the final pole in the string, taking care not to delete the wires, then replace the pole with a single telegraph pole(with connector assets) which can be manually joined to the bridge loft, wire by wire. A little time consuming, but worth the effort.
Hope this helps?