NER can restart this MG trains in BG right now.
A. 15301/02 Lucknow - Shahjahanpur-Pilibhit Express. Train was stopped during Shahjahanpur-Sitapur-Burhwal Gauge Conversion. Now can start via Daliganj-Sitapur Jn. Sitapur City Jn. - Shahjahanpur Jn. - Bisalpur-Pilibhit to Tanakpur.
B. 15303/04 Lalkuan - Shahjahanpur via Bhojipura - Pilibhit. Train was stopped during Shahjahanpur-Sitapur-Burhwal Gauge Conversion. Now can start as Kathgodum - Lucknow Nainital Express via Lalkuan-Bhojipura-Bareilly-Shahjahanpur-Sitapur-Daliganj to Lucknow/Aishbagh.
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15305/06 Bareilly City - Kanpur Anwarganj Kannyokubj Express via Kasganj-Farrukhabad. Train was stopped during Bareilly-Kasganj-Mathura & Kasganj-Farrukhabad-Kanpur Gauge conversion. Now can start via Badaun-Kasganj Jn. - Farrukhabad(Kampilyanagar)Jn. -Mainpuri Jn. -Etawah Jn. to Kanpur Central. Travelled once in 2005
7. 15307/08 Nainital Express. Train was stopped during Lucknow-Sitapur-Mailani-Pilibhit-Bareilly gauge conversion. Now can start operating via Daliganj-Sitapur-Shahjahanpur-Pilibhit-Bhojipura-Lalkuan & later shifted on original route via Daliganj-Sitapur-Lakhimpur-Mailani-Pilibhit-Bhojipura-Lalkuan post Mailani-Pilibhit gauge conversion. Travelled once in 2005.
9. 15309/10 Ruhelkhand/Rohilkhand Express. Train was stopped during Lucknow-Sitapur-Mailani-Pilibhit-Bareilly gauge conversion. Now can start via Balamau-Shahjahanpur-Bareilly Cantt - Badaun-Kasganj to Mathura Jn.
10. 15311/12 Kumaun Express:- Train was stopped during Bareilly-Kasganj-Mathura gauge conversion. Now 15055/56 running in its place to Ramnagar. Can be re-introduced to run from Agra Fort to Kathgodum via Achhnera-Mathura-Kasganj-Bareilly- Bhojipura-Lalkuan.
11. 15313/14 Originally was Mathura-Lucknow Express via Kasganj-Bareilly-Mailani-Sitapur. Can be re-introduced original route post Mailani-Pilibhit gauge conversion.
12. 5313A/5314A Link Service from Agra Fort to Kanpur Anwarganj during MG era. Train was stopped during Kasganj-Farrukhabad-Kanpur Gauge conversion. can be re-introduced via Achhnera-Mathura-Kasganj- Farrukhabad-Kanpur towards Banaras via PrayagRaj-Gyanpur Road.
13. 15315/16 Legendary Gokul Express. Running on Truncated Mailani-Dudhwa-Nanpara-Bahraich-Gonda route. Must be restarted as Agra Fort-Gorakhpur Gokul Express via Achhnera-Mathura-Kasganj-Bareilly-Pilibhit-Mailani-Sitapur-Burhwal-Gonda-Basti once Pilibhit-Mailani gauge conversion completed.
14. 15317/18 Pilibhit-Shahjahanpur Express. Stopped running due to Shahjahanpur-Pilibhit gauge conversion. Must be restarted from Tanakpur to Lucknow via Pilibhit-Shahjahanpur.
15. 15319/20 Sanctuary Express. Train can be restarted as Mailani-Anand Vihar Terminal Overnight Sanctuary Express via Sitapur-Daliganj-Aishbagh-Kanpur-Etawah-Tundla-Aligarh.
16. 15321/22 Kapilavastu Express. Stopped running due to Gorakhpur-Gonda Loop line gauge conversion. Must get restarted as Gorakhpur-Agra Cantt. Kapilavastu Express via Barhni-Gonda-Lucknow-Kanpur-Kasganj-Mathura.

NER can restart its Legendary MG trains in BG easily. But they lack willpower or deliberately unwilling to restart these trains.