Keir Starmer is whisking his top 100 prospective parliamentary candidates to Stratford-on-Avon this weekend for a crash course in message discipline, media training and the art of campaigning. The Labour leader will be hoping they gain communications inspiration in the birthplace of William Shakespeare as the party trains them in its election strategy. Candidates will be encouraged to network with others in their region so they can share notes on what issues in their areas should be their priority. They will hear from senior Labour figures including the shadow business secretary, Jonathan Reynolds. “It’s about making sure there are no bruises to press and that everyone is singing from the same hymn sheet,” a source said. “But it’s clear that HQ are just laser-focused on winning.” Starmer’s top team want the candidates to feel part of the team before party conference and ready to adopt their vision of “building a better Britain” if they win power. Insiders have claimed Morgan McSweeney, Labour’s campaign manager, is regularly in touch with candidates, with one saying he was so keen to ensure the candidates maintained a “squeaky clean” record before the election that he had warned them of actions that could lead to them losing the whip under a Labour government. Senior party figures say they want to avoid repeating mistakes of the past, with sources claiming candidates were selected very early on before the 2015 election and “left in the wilderness”. Recalling what it was like after winning selection, a frontbencher said: “It can be quite lonely. You’re literally your own boss running your own mini-operation. No one really tells you how to do these things.” Labour to Win, a party-affiliated network focused on bolstering Starmer’s leadership, is understood to have provided networking and training opportunities for most of the selected candidates, who are not shy of being “pro-Starmer”, according to an insider. A leftwing source welcomed the support for candidates but added: “It would have been better if many of them were democratically selected in the first place.” The source said: “It’s pretty rich for the right to give lectures when we’ve seen mass activists, resignations and dissolution at the grassroots across the country in the wake of Starmer’s stitch-ups. This disdain for local members and parties is leaving Labour weakened at the grassroots just when we need members to knock on doors come the general election.” Senior Labour officials are understood to not be complacent over the diversity of the top 100 candidates, and are proud of the quality of candidates, believing none of them can be deemed “trouble”. In March, a senior official noted that 18% of candidates were from minority ethnic backgrounds, a record for the party. The training retreat follows months of turmoil within the party over selections. Members of Starmer’s shadow ministerial team have been pitted against junior leftwing MPs in battles to win the nomination for new parliamentary seats. Gerald Jones, the shadow Welsh minister, won a selection contest for the new seat of Merthyr Tydfil and Upper Cynon on Wednesday against Beth Winter, an MP from the leftwing Socialist Campaign group. Alison McGovern, a shadow work and pensions minister, won against Mick Whitley, another leftwing MP in the Socialist Campaign group in the seat of Birkenhead, where the boundaries were redrawn. • This article was amended on 31 July 2023. The reference to sources claiming that candidates were selected very early on before the 2017 election, should have referred to the 2015 election.